Afghanistan is the opium exporter of the world. They grow and farm large quantities of poppy in order to achieve this. Much to the chagrin of Europe, Afghanistan continues to export huge amounts of opium, even after the EU has told them to stop.
Mostly in Oil. They aren't known much for manufacturing, but that is another factor of their economy.
The major pillar of a country is called as the major economic activities. For example in Hawaii the major economic activity is Tourism.
What were the major economic activities of Los Angeles
Agriculture
tobacco
Tobacco
aquaculture
selling cheese is a large economic activity
aquaculture
Oil and Gas.
Major economic activities in the Persian Gulf and interior areas of the region include oil production, farming, and gas production.
wheat , corn & fishing .
they may vary